Field of the Invention
The present invention relates to a technique of performing navigation display for searching for the position of a lesion using an image obtained by an imaging apparatus such as an ultrasonic imaging apparatus.
Description of the Related Art
In the medical field, a doctor displays, on the monitor, a medical image obtained by capturing a target object, interprets the displayed medical image, and diagnoses the lesion site.
Medical image collecting apparatuses (to be referred to as modalities hereinafter) for capturing a medical image include an ultrasonic image diagnostic apparatus, a resonant magnetic coupling imaging apparatus (to be referred to as an MRI apparatus hereinafter), and an X-ray computed tomography apparatus (to be referred to as an X-ray CT apparatus hereinafter). It is difficult to accurately diagnose the state of a lesion site by only observing a medical image captured by an individual modality. Hence, an attempt has been made to accurately diagnose the state of a lesion site by comparing lesion sites in medical images captured by a plurality of modalities or medical images captured on or at different dates and times.
In diagnosis based on a plurality of medical images, for example, while looking at the image of a lesion site (to be referred to as a lesion site of interest hereinafter) indicated in one medical image (to be referred to as a reference image hereinafter), the operator searches another medical image (to be referred to as a target image hereinafter) for a lesion site (to be referred to as a corresponding lesion site hereinafter) corresponding to the lesion site of interest, and specifies it.
Japanese Patent Laid-Open No. 2008-279272 discloses a method in which a square having a size and color based on the distance and direction of an image track point (lesion site of interest), which is selected from a past ultrasonic tomogram, from a current ultrasonic tomogram is superimposed and displayed as an in-plane indicator on the current ultrasonic tomogram. Japanese Patent Laid-Open No. 2008-279272 further discloses a technique of selecting whether to hide or remove all or some in-plane indicators from the display.
In some cases, an alignment error is generated due to the difference in imaging posture between different medical images, or a position-specifying error is generated for a region of interest such as a lesion site. It is conceivable to present an “existence region” where a region of interest may exist.
In addition, when a plurality of regions of interest exist, the relationship between them should be grasped. However, if a plurality of existence regions are displayed on an ultrasonic tomogram, it is hard for the observer to recognize an existence region where the current region of interest exists. This may affect efficient diagnosis.